1. Field of the Invention
This invention relates to wind driven turbines. More particularly, this invention relates to a turbine designed to capture a maximum amount of energy from wind to drive an electrical generator.
2. Background Information
Wind driven turbines and windmills have been used for centuries to capture energy and generate power. There have been constant efforts to increase the efficiency and hence the energy production of wind turbines. The goal of many wind turbine designs has been to obtain power in greater or lessor quantities without making the apparatus cumbersome, expensive or overly complex.
Some turbines have been developed that use fan blade wheels to drive a shaft to produce energy, while other turbines use rotors connected to a shaft. For example, wind driven generators consisting of rotors having a plurality of parallel vanes arranged circumferentially around a vertical axis have been used to drive generators. Housings have been developed to surround the rotors to capture the wind and direct the airflow to increase the efficient use of the energy of the captured wind to push the rotors. See U.S. Pat. No. 5,332,354, issued to Lamont on Jul. 26, 1994, and U.S. Pat. No. 5,447,412, issued to Lamont on Sep. 5, 1995. The Lamont patents show a unique wind turbine design containing a housing enclosing a turbine means and a baffle to direct the wind to drive the blades of the turbine in varying locations. These designs advantageously capture the atmospheric power source to drive the blades of the turbine in more than one location. Other turbine designs have been developed with housings rotatably mounted on support structures with vanes that direct the housing, and hence the blades, to the direction of the oncoming wind.
A variety of wind turbines have also been designed with converging inlet passages that increase the velocity of the wind, and hence decrease the pressure in the passage, as the inlet passage narrows. See U.S. Pat. No. 4,132,499, issued to Igra on Jan. 2, 1979, and U.S. Pat. No. 4,178,124, issued to Puskas on Dec. 11, 1979. The Igra and Puskas patents show a converging conical inlet used to capture wind for the wind turbines that increase the velocity of the wind as it moves toward the turbines.
The prior art wind turbines have a number of disadvantages. One disadvantage is that a number of wind turbine designs that use a housing to enclose the turbine blades do not capture a maximum amount of energy from the airflow. Another disadvantage of a number of prior art devices is that they lack simplicity. Complex turbine designs or turbines with a large number of parts are likely not only to be more expensive, but also more prone to failure. Another disadvantage of a number of the prior art wind turbines is that they are not easily adjustable for use in differing wind conditions. If a turbine designed for use in low wind velocities is subjected to high winds, therefore, it may be prone to failure or damage. Similarly, if a turbine designed for use in high wind velocities is subjected to low velocities, it will produce only small amounts of energy.
A need exists for a wind turbine that captures a maximum amount of the wind energy caught by a housing enclosing turbine blades, utilizes a simple design to contain the cost of the wind turbine and decrease the risk of failure, and adjusts readily so that it may be used in different geographic areas or in varying wind conditions without harm to the wind turbine.